Safety and Efficacy of Combined Ruxolitinib and Decitabine in Accelerated and Blast-Phase Myeloproliferative Neoplasms

Blood Adv. 2018 Dec 26;2(24):3572-3580. doi: 10.1182/bloodadvances.2018019661.

Abstract

Myeloproliferative neoplasms (MPN), including polycythemia vera, essential thrombocythemia, and primary myelofibrosis, have a propensity to evolve into accelerated and blast-phase disease (MPN-AP/BP), carrying a dismal prognosis. Conventional antileukemia therapy has limited efficacy in this setting. Thus, MPN-AP/BP is an urgent unmet clinical need. Modest responses to hypomethylating agents and single-agent ruxolitinib have been reported. More recently, combination of ruxolitinib and decitabine has demonstrated synergistic in vitro activity in human and murine systems. These observations led us to conduct a phase 1 study to explore the safety of combined decitabine and dose-escalated ruxolitinib in patients with MPN-AP/BP. A total of 21 patients were accrued to this multicenter study. Ruxolitinib was administered at doses of 10, 15, 25, or 50 mg twice daily in combination with decitabine (20 mg/m2 per day for 5 days) in 28-day cycles. The maximum tolerated dose was not reached. The most common reasons for study discontinuation were toxicity/adverse events (37%) and disease progression (21%). Fourteen patients died during study treatment period or follow-up. The median overall survival for patients on study was 7.9 months (95% confidence interval, 4.1-not reached). Among evaluable patients, the overall response rate by protocol-defined criteria (complete remission with incomplete count recovery + partial remission) was 9/17 (53%) and by intention-to-treat analysis was 9/21 (42.9%). The combination of decitabine and ruxolitinib was generally well tolerated by patients with MPN-AP/BP and demonstrates potentially promising clinical activity. A phase 2 trial evaluating the efficacy of this combination regimen is ongoing within the Myeloproliferative Disorder Research Consortium.

Publication types

  • Clinical Trial, Phase I
  • Multicenter Study
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Antineoplastic Agents / adverse effects
  • Antineoplastic Agents / pharmacokinetics
  • Antineoplastic Agents / therapeutic use*
  • Blast Crisis
  • Decitabine / adverse effects
  • Decitabine / pharmacokinetics
  • Decitabine / therapeutic use*
  • Dose-Response Relationship, Drug
  • Drug Administration Schedule
  • Drug Therapy, Combination
  • Female
  • Half-Life
  • Hematologic Diseases / etiology
  • Humans
  • Male
  • Middle Aged
  • Myeloproliferative Disorders / drug therapy*
  • Myeloproliferative Disorders / pathology
  • Pyrazoles / adverse effects
  • Pyrazoles / pharmacokinetics
  • Pyrazoles / therapeutic use*
  • Treatment Outcome

Substances

  • Antineoplastic Agents
  • INCB018424
  • Pyrazoles
  • Decitabine